AU2021201701B2

AU2021201701B2 - Battery pack for an electrical appliance

Info

Publication number: AU2021201701B2
Application number: AU2021201701A
Authority: AU
Inventors: Markus Thannhuber
Original assignee: Einhell Germany AG
Current assignee: Einhell Germany AG
Priority date: 2020-04-01
Filing date: 2021-03-17
Publication date: 2023-01-12
Anticipated expiration: 2041-03-17
Also published as: AU2021201701A1; AU2021201701C1; EP3890100B1; EP3890100C0; DE102020109105A1; EP3890100A1

Abstract

A battery pack (1) for an electrical appliance having an improved sealing against penetrating liquid comprises an outer housing (2a, 2b) with a bottom shell (2a) as well as a top shell (2b). 5 The battery pack (1) comprises a battery cell (3), which is arranged in the bottom shell (2a), as well as a circuit carrier (4, 7) and a sealing element, which is arranged between the top shell (2b) and the circuit carrier (4, 7). The sealing element (5) separates a first spatial region (6a) within the outer housing (2a, 2b) in a liquid-tight manner from a second spatial region (6b) within the outer housing (2a, 2b). The first spatial region (6a) is open towards an 0 external environment of the battery pack (1) with respect to an exchange of liquid. (Fig. 4) 17512014_1 (GHMatters) P115785.AU 1/4 12 14 4 17 Fa 18g Fig. 1 12 14 9 11 19 16 39 Fig.2

Description

1/4

12 14 4

17 18g Fa

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Battery Pack for an Electrical Appliance

DESCRIPTION:

The invention relates to a battery pack for an electrical appliance, an electrical appliance comprising such a battery pack as well as a method for manufacturing a battery pack for an electrical appliance.

Battery packs for electrical appliances, for example electric power tools, are frequently detachably attached to the electrical appliances in such a way that the battery packs can be detached from the electrical appliance for charging. This moreover has the advantage that the electrical appliance can be powered by a further battery pack also during charging the first battery pack. Moreover, if given, various electrical appliances can be powered by the same battery pack.

In the case of such battery packs, however, the electrical contact elements necessarily are in contact with the environment of the battery pack since an electrical contact between battery pack and electrical appliance has to be established. As a consequence, water can penetrate the interior of the battery pack and there may possibly come into contact with the circuit electronics of the battery pack and/or the battery cells of the battery pack, which in turn may lead to a defect of the battery pack.

In document EP 2 487 736 A1 a battery for an electric power tool is described, in which a circuit board is fixed to a housing for instance by screws. A sealing element is provided, which is arranged between the circuit carrier and the battery housing and surrounds electronic components mounted on the circuit carrier. Thereby the battery cell itself, however, is not protected against penetrating water. Moreover, only certain parts of the circuit carrier are protected.

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Document US 2018/0366697 Al describes a battery pack comprising an outer housing and a cell module. The cell module is coated with a hydrophobic nano coating. The circuit electronics of the battery pack, however, is not protected against penetrating water by the nano coating.

Against this background it is desirable that embodiments of the present invention provide an improved concept for a battery pack for an electrical appliance, by which concept the electric components in the interior of the battery pack can be protected more reliably against penetrating water.

According to the embodiments of the present invention it is desirable that the improved concept is provided by the respective subject matter of the independent patent claims. Further embodiments and preferred designs are subject matter of the dependent patent claims.

The improved concept is based on the idea of arranging between a top shell of an outer housing of the battery pack and a circuit carrier of the battery pack a sealing element separating a first spatial region within the outer housing from a second spatial region within the outer housing, wherein the first spatial region is open towards the environment of the battery pack.

According to an aspect of the present invention there is provided a battery pack for an electrical appliance, wherein the battery pack comprises an outer housing comprising a bottom shell and a top shell. The bottom shell comprises a bottom. The battery pack comprises at least one battery cell arranged in the bottom shell. The battery pack comprises a circuit carrier arranged on a side of the at least one battery cell facing away from the bottom. The battery pack comprises a sealing element arranged between the top shell and a side of the circuit carrier facing away from the bottom, wherein the sealing element separates a first spatial region within the outer housing in a liquid-tight manner from a second spatial region within the outer housing. The first spatial region is open towards an external environment of the battery pack with respect to an exchange of liquid on a surface of the circuit carrier facing away from the bottom a sealing layer made of a liquid-tight material is arranged, which extends both in the first spatial region as well as in the second spatial region; and the sealing element is in direct contact with the sealing layer for liquid-tight separation of the first spatial region from the second spatial region.

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The circuit carrier may also be referred to as carrier for electronic components or as circuit board or printed circuit board.

The fact that the circuit carrier is arranged on the side of the battery cell facing away from the bottom does not necessarily mean that the circuit carrier is in direct contact with the battery cell. Rather, the term "side" merely refers to a direction or a spatial region with respect to the battery cell. In other words, the side is not identical in meaning with a surface of the battery cell.

The outer housing of the battery cell may for instance have a substantially cuboid-shaped basic shape. In particular the top shell and the bottom shell each may have a base area or base plate as well as a wall extending perpendicularly relative to the respective base plate and surrounding same circumferentially. In the mounted state, the base plates of the top shell and the bottom shell are for instance arranged in parallel or substantially in parallel to each other. The base plate of the bottom shell in this connection can be referred to as bottom of the bottom shell, and the base plate of the top shell can for instance be designated as cap of the top shell.

The fact that the at least one battery cell is arranged in the bottom shell can for instance be understood in such a way that the at least one battery cell in each case is arranged at least in part in the bottom shell. This, however, does not exclude that the at least one battery cell also projects beyond the bottom shell, in particular beyond the wall of the bottom shell, and in the mounted state can accordingly be arranged in part in the top shell or extend into the top shell.

The term "liquid-tight" can in particular be understood as water-tight. A liquid-tight connection according to this understanding is in any case water-tight, however, may also be designed to be tight against further liquids and/or gases. In particular "liquid-tight" may also include water tight as well as air-tight.

In other words, the sealing element can separate the first spatial region in a gas- and liquid tight, in particular air- and water-tight or in any case water-tight manner from the second spatial region.

The sealing element seals the first spatial region in particular with regard to the second spatial region. In other words the sealing element in the mounted state of the battery pack is

17488002_1 (GHMatters) P115738.AU in mechanical interaction with the top shell or the circuit carrier and/or other components of the battery pack so that the liquid-tight separation of the spatial regions results. In other words, if the sealing element were not present, the first spatial region would not be separated from the second spatial region in a liquid-tight manner.

The sealing element in this connection may for instance be in direct contact with the top shell.

Here and in the following the mounted state of the battery pack relates in particular to a state in which the battery pack itself is fully mounted and the top shell is connected with the bottom shell so that the outer housing is closed. In the mounted state the battery pack consequently is not necessarily fixed to the electrical appliance.

The external environment of the battery pack can in particular be regarded as environment external to the outer housing. This may also be considered as definition of the outer housing. In other words, the outer housing spatially separates the battery pack, in particular the at least one battery cell and the circuit carrier, from the external environment of the battery pack.

Whilst the first spatial region is separated from the second spatial region in a liquid-tight manner, it may be the case that the at least one battery cell and/or the circuit carrier or electronic components mounted on the circuit carrier are separated from the second spatial region in a manner that is not liquid-tight. In other words, if hypothetically a liquid were present in the second spatial region, it could not be excluded that the liquid also comes into direct contact with the at least one battery cell and/or the electronic components. According to the improved concept, by the sealing element liquid is prevented from penetrating the second spatial region from outside the outer housing.

On the circuit carrier various electronic components may be mounted for operating the battery pack and/or the electrical appliance. For instance the circuit carrier may carry logical circuits or measurement circuits and/or sensor components. The sensor components for instance can comprise a current and/or a voltage sensor and so on, and the measurement circuits can be configured for evaluating the corresponding sensor signals.

The electronic components may also serve for voltage control or for communication of the battery pack with the electrical appliance. The electronic components may for instance also

17488002_1 (GHMatters) P115738.AU include a battery management system, BMS, of the battery pack. In particular the electronic components may also include one or several power switches, for instance power transistors, in order to switch a current flow from the at least one battery cell to the electrical appliance.

The electrical appliance may in particular be an appliance, which is to be electrically supplied by the battery pack, in particular by the energy stored in the at least one battery cell, that is for instance an electrical household appliance, an electric power tool, or an electric motor, for instance for an electrically powered bicycle.

The electrical appliance, however, may also correspond to an appliance providing electrical energy to the at least one battery cell, that is for instance a charging device for the battery pack.

By the liquid-tight separation of the first spatial region from the second spatial region according to a battery pack according to the improved concept it is prevented that liquid, in particular water, which penetrates the first spatial region from outside the outer housing, because the first spatial region necessarily is open towards the external environment, penetrates the second spatial region and in this way comes into contact with electric components on the circuit carrier or with the at least one battery cell. Thereby the functional safety of the battery pack is increased and damage to or destruction of the battery pack or the electrical appliance is prevented.

By the first spatial region with respect to an exchange of liquid being open towards the external environment, penetrated water can also drain from the outer housing again. Thereby it is prevented that in the long run accumulations of water in the interior of the outer housing occur.

By the arrangement of the sealing element between the top shell and the side of the circuit carrier facing away from the bottom a particularly space-saving arrangement is facilitated so that in particular no enlarged construction space of the battery pack is required to improve the safety or sealing of the battery pack as described.

According to at least one embodiment of the battery pack according to the improved concept the second spatial region towards the external environment of the battery pack is closed with respect to an exchange of liquid.

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According to at least one embodiment the second spatial region towards the at least one battery cell is open with respect to an exchange of liquid.

According to at least one embodiment the battery pack comprises a cell holder which is arranged at least in part in the bottom shell and holds the at least one battery cell.

According to at least one embodiment the sealing element comprises a volume-adjusting sealing material, for instance an elastomer or a foam material, in particular a soft foam material.

According to at least one embodiment at least one power switch, in particular a power transistor, is arranged in the second spatial region and electrically connected to the circuit carrier or mounted on the circuit carrier, respectively.

According to at least one embodiment the battery pack comprises a locking mechanism for mechanically fastening or unfastening the battery pack to the electrical appliance. The locking mechanism is at least in part arranged in the first spatial region. In particular a movable component of the locking mechanism is arranged at least in part in the first spatial region.

Besides contact elements for electrical contacting of the electrical appliance with the battery pack also the locking mechanism necessarily at least in part is in contact with the external environment since it has to be capable of being activated by a user. Accordingly also the movable component of the locking mechanism represents a potential possibility for penetrating water. By the arrangement in the first spatial region also water penetrated in this way is kept away from the second spatial region.

According to at least one embodiment the battery pack comprises a further sealing element, which is arranged between the top shell and the side of the circuit carrier facing away from the bottom and which separates the first spatial region in a liquid-tight manner from a further second spatial region within the outer housing.

The further second spatial region may for instance be open towards an electronic component on the circuit carrier with respect to an exchange of liquid.

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According to at least one embodiment the battery pack comprises a sealing layer, which is arranged on a surface of the circuit carrier, in particular a base plate of the circuit carrier, facing away from the bottom.

For instance the top shell can press the sealing element to the sealing layer.

The surface of the circuit carrier facing away from the bottom may in particular be considered as integral part of the circuit carrier so that the sealing layer is in direct contact with this surface.

The sealing layer may also be considered as part of the circuit carrier.

The sealing layer contains for instance a plastic material or a potting material, in particular a water-tight and hydrophobic material, or consists of such material.

The sealing layer may contain in particular a silicone and/or a polyurethane.

The sealing layer may also be designated or designed as thick film.

In particular the sealing layer may pot or surround in a liquid-tight manner one or several electronic components, which are mounted on the circuit carrier, in particular on the base plate, so that from the first and/or the second spatial region no liquid can reach these electronic components.

By the sealing layer the surface of the circuit carrier, in particular the base plate, is sealed in a water-tight manner so that a raised protection for the electronic components against penetrating water is ensured. Moreover, the sealing layer offers an ideal substrate for the sealing element by creating a homogenous, plane and tight touch surface between the sealing element and the circuit carrier. Thereby the liquid-tight separation between the first and the second spatial region can be realized particularly reliably.

According to at least one embodiment the sealing layer, alone or in combination with a further sealing component of the battery pack, completely covers the surface of the circuit carrier facing away from the bottom, in particular of the base plate, within the first spatial region.

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According to at least one embodiment the battery pack comprises a boundary element, which is applied or arranged on the side of the base plate of the circuit carrier facing away from the bottom, in particular along an edge of the base plate. By the boundary element a region on the side of the base plate facing away from the bottom is defined, which is covered by the sealing layer or potted by the material of the sealing layer.

For instance the sealing layer in combination with the boundary element can completely cover the circuit carrier or the surface of the circuit carrier or of the base plate, respectively, facing away from the bottom, respectively, in the first spatial region.

The boundary element therein may be designed as sealing bead.

According to at least one embodiment the sealing element is connected with the top shell in a materially bonded manner, for instance glued together with the top shell.

According to at least one embodiment the sealing element is connected with the sealing layer in a force-fitting manner, consequently is pressed in particular by the top shell to the sealing layer.

According to at least one embodiment the top shell comprises a web, which is arranged in particular on an inner surface of the top shell, and the sealing element is arranged between the web and the sealing layer.

According to at least one embodiment the sealing element is pressed by the web to the sealing layer.

The sealing element may for instance be connected to the web in a materially bonded manner, for instance glued together with the web.

The web may for instance be designed as projection of the top shell into the interior of the outer housing.

By the web force can be applied specifically to the sealing element in such a way that a continuous sealing and a tight connection between the sealing element and the sealing layer is achieved.

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The force may for instance be achieved by a connection of the top shell with the bottom shell, for instance a clamping connection or a snap-in connection.

According to at least one embodiment the sealing element comprises a sealing bead or consists of one or several sealing beads.

Thereby it is in particular facilitated to apply the sealing element in a highly automated manner and to realize nearly any random spatial courses of the sealing bead. In particular the sealing element may also extend three-dimensionally.

For instance the sealing element may be designed as formed in-place foam gasket. The process of applying such sealing bead accordingly is also referred to as "FIPFG".

The sealing bead may in particular be applied along the web to the top shell or along a defined path to the top shell or to the sealing layer, respectively.

According to at least one embodiment the sealing element comprises a foam material, that is a foamed material, in particular a plastic foam, for instance a polyurethane foam or a silicone foam.

The sealing element therefore can also be designed as sealing foam and in corresponding embodiments as sealing foam bead or foam bead.

In particular the foam material is a single-component foam material.

In such embodiments a particularly simple processing and manufacturing of the battery pack is possible. In particular in the case of single-component materials, if given, no chemical curing is required, which facilitates a simplified process control in the manufacture of the battery pack.

By using a foam material the sealing element may be designed as a volume-adjusting and groutable sealing element, which settles particularly tightly on the sealing layer. In this way, if given, irregularities in the sealing layer may be compensated for.

According to at least one embodiment the battery pack comprises a contact unit for electrical contacting of the electrical appliance, in particular for electrical contacting of the electrical

17488002_1 (GHMatters) P115738.AU appliance with the battery pack and the at least one battery cell. The contact unit is arranged in the first spatial region or in part in the first spatial region on the circuit carrier.

In particular the contact unit is electrically connected to the circuit carrier, in particular the base plate of the circuit carrier.

The contact unit may for instance be electrically connected exclusively in the first spatial region with the circuit carrier or the base plate, respectively, and an electrical contacting of the contact unit with the circuit carrier may be effected entirely outside the second spatial region.

The contact unit may for instance comprise one or several contact elements for electrically contacting of the electrical appliance with the at least one battery cell and/or other components on the circuit carrier. The contact elements may for instance be designed as clamp contacts, sword contacts, or tulip contacts. The contact unit may also be designed as clamp block.

The contact unit may in particular extend in part perpendicularly to the circuit carrier and in particular also project in part from the spatial region in order to facilitate the electrical contacting with the electrical appliance.

The contact unit, as described above, necessarily is in contact with the external environment of the battery pack. By such embodiments the contact unit can be safely separated from the second spatial region so that water possibly penetrating the first spatial region via the contact unit nevertheless is kept away from the electronic components on the circuit carrier and/or the at least one battery cell.

According to at least one embodiment the battery pack contains a foam part covering, for instance fully covering, the contact unit against the external environment, unless the contact unit is contacted, that is if the battery pack is separated from the electrical appliance. The foam part comprises at least one insertion slot for inserting a contact element of the electrical appliance into a corresponding contact element of the contact unit.

The fact that the contact unit is covered by the foam part against the external environment, may in particular be understood in such a way that no direct contact exists between the

17488002_1 (GHMatters) P115738.AU contact unit or the contacts of the contact unit, respectively, and the external environment of the battery pack.

In the non-contacted state the insertion slots are in particular closed. If the contact element of the electrical appliance, which may for instance be designed as sword contact or the like, is inserted into the insertion slot, water that is possibly present on the contact element of the electrical appliance can be wiped off by the foam part.

Thereby the amount of liquid introduced via the contact unit into the spatial region is reduced.

According to at least one embodiment the foam part contains a closed porous material and is in particular designed to be water-tight.

According to at least one embodiment the insertion slots are configured to be self-sealing.

According to at least one embodiment the outer housing comprises one or several drainage openings through which a liquid can drain from the first spatial region into the external environment.

It is thereby avoided that a long term accumulation of liquid in the first spatial region occurs.

According to the improved concept also an electrical appliance comprising a battery pack according to the improved concept is provided.

According to another aspect of the present invention there is also provided a method for manufacturing a battery pack for an electrical appliance. A bottom shell for an outer housing for an electrical appliance is provided, wherein the bottom shell comprises a bottom. At least one battery cell is arranged in the bottom shell. A circuit carrier is arranged on a side of the at least one battery cell facing away from the bottom, and a top shell is provided for the outer housing. A sealing element is arranged between the top shell and a side of the circuit carrier facing away from the bottom, and the top shell is connected with the bottom shell. The sealing element therein is arranged in such a way that it separates a first spatial region within the outer housing in a liquid-tight manner from a second spatial region within the outer housing, after or when the top shell is or has been connected with the bottom shell. The first spatial region therein is open towards an external environment of the battery pack with respect to an exchange of liquid; a boundary element is applied to a side of a base plate of

17488002_1 (GHMatters) P115738.AU the circuit carrier; a portion of the side of the base plate facing away from the bottom, which is bounded at least in part by the boundary element is coated with a potting material in order to create a sealing layer; the coated portion extends both in the first spatial region as well as in the second spatial region. The connection of the top shell with the bottom shell may in particular be effected in a materially bonded or form-fitting manner. For instance the top shell may be glued together with the bottom shell.

It is pointed out that the named method steps are not necessarily performed in the named order, but rather can also be performed in a different, technically reasonable order.

The form-fitting connection of the top shell with the bottom shell may for instance be effected by one or several clamp connections or snap-in connections.

In various embodiments the top shell and the bottom shell may also be pivotably connected with each other by one or several hinges so that the outer housing can be opened in a simple and non-destructive way.

According to at least one embodiment of the method according to the improved concept at least a part of the sealing element is applied as sealing bead to the circuit carrier or to the top shell.

In particular the sealing element is applied by FIPFG to the circuit carrier or the top shell.

Such methods are characterized by a particularly high and flexible degree of automation capability.

According to at least one embodiment an, in particular liquid-tight, boundary element is applied to a side of a base plate of the circuit carrier facing away from the bottom, in particular along an edge of the base plate.

The sealing element can for example be applied as sealing bead to the sealing layer.

The boundary element therein may for instance be designed as further sealing bead, in particular made of a foam material, in particular a silicone foam or a polyurethane foam, and may for instance equally be applied by FIPFG.

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By the boundary element the portion to be potted can be exactly defined so that a specific and reliable coating of the base plate with the sealing layer can be achieved.

According to at least one embodiment the sealing element is grouted, in particular by the connecting of the top shell with the bottom shell, between the top shell and the sealing layer or pressed by the top shell to the sealing layer.

According to at least one embodiment the sealing element is applied to the sealing layer in order to arrange the sealing element between the top shell and the side of the circuit carrier facing away from the bottom.

According to at least one embodiment the sealing element is applied to the top shell in order to arrange the sealing element between the top shell and the side of the circuit carrier facing away from the bottom.

According to at least one embodiment the sealing element is arranged between the sealing layer and a web of the top shell.

According to at least one embodiment the sealing element, in particular the sealing bead, is applied to the web.

By applying the sealing element as sealing bead to the web and pressing it subsequently to the sealing layer, a position of the sealing element can be precisely determined and thus a precise spatial definition of the first spatial region be realized.

According to at least one embodiment the sealing element is pressed by the web to the sealing layer, in particular after or by connecting the top shell with the bottom shell.

Further embodiments of the method according to the improved concept directly derive from the various embodiments of the battery pack according to the improved concept and vice versa.

The features and feature combinations mentioned previously in the description as well as the features and feature combinations mentioned in the following in the description of the figures and/or shown in the figures alone are not only employable in the respective indicated combination but also in other combinations, without leaving the scope of the improved

17488002_1 (GHMatters) P115738.AU concept. Also implementations and feature combinations are to be regarded as disclosed which do not comprise all features of an originally formulated independent claim and/or go beyond the feature combinations set out in the back-references of the claims or deviate therefrom.

In the following the embodiments of the invention are explained in more detail by reference to concrete embodiments and associated schematic drawings. In the figures same elements and elements having the same function can be equipped with the same reference signs. The description of identical or functionally identical elements, if given, is not necessarily repeated with regard to various figures.

In the figures show:

Fig. 1 a schematic view of a part of an exemplary embodiment of a battery pack according to the improved concept as well as a method step according to an exemplary embodiment of a method according to the improved concept;

Fig. 2 a schematic view of a part of an exemplary embodiment of a battery pack according to the improved concept as well as a method step according to an exemplary embodiment of a method according to the improved concept;

Fig. 3 a schematic view of a part of an exemplary embodiment of a battery pack according to the improved concept as well as a method step according to an exemplary embodiment of a method according to the improved concept;

Fig. 4 a schematic view of a part of an exemplary embodiment of a battery pack according to the improved concept as well as a method step according to an exemplary embodiment of a method according to the improved concept;

Fig. 5 a schematic view of a part of an exemplary embodiment of a battery pack according to the improved concept as well as a method step according to an exemplary embodiment of a method according to the improved concept;

Fig. 6 a schematic view of a part of an exemplary embodiment of a battery pack according to the improved concept as well as a method step according to an exemplary embodiment of a method according to the improved concept;

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Fig. 7 a schematic view of an exemplary embodiment of a battery pack according to the improved concept as well as a further step of a method according to an exemplary embodiment according to the improved concept; and

Fig. 8 a sectional view through the battery pack of Fig. 7.

In Fig. 1 to Fig. 8 exemplary embodiments of a battery pack 1 or parts of the battery pack 1 according to the improved concept, respectively, are schematically shown. Figs. 1 to 8 may also be considered as various intermediate stages in the manufacturing of a battery pack 1 according to a method according to the improved concept.

In Fig. 7 the completed battery pack 1 in the fully mounted state is shown. The battery pack 1 comprises an outer housing with a bottom shell 2a and a top shell 2b. A push button 13 for unlocking a connection between an electrical appliance (not shown) and the battery pack 1 is provided.

The bottom shell 2a may for instance consist of a single-part or multi-part plastic body housing in particular at least one battery cell 3. The at least one battery cell 3 therein may for instance be held by a cell holder 16 (see Fig. 1, Fig. 2, Fig. 4, as well as Fig. 8).

In Fig. 1 the bottom shell 2a is shown, wherein the at least one battery cell 3 is arranged in the cell holder 16 in the bottom shell 2a.

The top shell 2b in Fig. 1 is not yet attached. A circuit board 4 is arranged on a side of the at least one battery cell 3 or the cell holder 16, respectively, facing away from the bottom. For instance the circuit board 4 may be connected to the cell holder 16 by screw joints or other connections. These screw joints may in particular be sealed against penetrating water. Also the cell holder 16 may for instance be sealed against the outer housing 2a, 2b.

On the circuit board 4, in particular on the side of the circuit board 4 facing away from the bottom, electronic components 14, 18, 19 may be mounted, of which for the sake of clarity only individual ones are shown.

The electronic components 14, 18, 19 may for instance include a push button 14, power MOSFETs 19 and/or other electronic components 18.

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On the surface of the circuit board 4 moreover connection contacts 17 for contacting a contact unit 9 (see Fig. 2) are provided.

The battery pack 1 may also comprise a locking mechanism 12, by the mechanical activation of which, for instance by means of a push button 13, the battery pack 1 can be separated from the electrical appliance.

In Fig. 1 moreover a first sealing bead is shown, which for instance may be applied along an edge of the circuit board 4 and for instance may consist of a silicone-based or polyurethane based foam material. By the sealing bead therefore a boundary element 11 is created which defines a portion on the surface of the circuit board 4.

Thereafter, this portion may be coated by a potting material in order to create a sealing layer 7, which covers the surface in the accordingly defined portion.

The contact unit 9 may be mounted in particular prior to the applying of the potting material.

By the sealing layer 7 part of the electronic components 18 may for instance be completely potted. Other components, such as for instance the push button 14 or the power MOSFETs 19, for instance may, however, be uncovered.

The sealing layer 7 may for instance be applied via a mechanically positioned applicator to the circuit board 4. The sealing layer 7 therein may equally contain silicone- or polyurethane based material or consist thereof. Thereby a water-tight and water-repellent coating is created.

The potting material therein is in particular chosen in such a way that during applying it is at least viscous and covers the corresponding component structures on the circuit board 4 in such a way that a surface that is as homogenous as possible develops in large portions on the circuit board 4.

In the portion of the contact unit 9, if given, different application nozzles may be used in order to apply the coating in such a way that the contact unit 9 is laterally fully enclosed. Thereby, penetrating water, in particular water penetrating the interior of the outer housing 2a, 2b via

17488002_1 (GHMatters) P115738.AU the contact unit 9, may drain via the contact unit 9 and does not reach the circuit board 4 underneath in particular through the contact unit 9.

After the sealing layer 7 has been applied, a sealing element 5 is applied to the sealing layer 7, in particular in the form of a foam bead, as shown in Figs. 3 and 4.

In the shown embodiment the sealing element 5 in part is also arranged in the region of the locking mechanism 12.

Depending on the embodiment of the method, the sealing element 5, however, may also be applied to the top shell 2b, in particular to a web 8 of the top shell 2b, as it is schematically shown in Figs. 6 and 8.

The sealing element 5 may for instance be applied along a recess for the housing lock of the top and the bottom shell 2a, 2b as well as in the region of corresponding recesses for the contact unit 9, as equally evident from the course of the web 8 in Fig. 6.

The foam bead therein is applied substantially in the horizontal direction, however, in particular in the region of the locking mechanism 12, may also extend diagonally or vertically relative to the top shell 2b or the bottom of the bottom shell 2a.

By connecting the top shell 2b with the bottom shell 2a in order to close the outer housing 2a, 2b, the sealing element 5 is grouted against the sealing layer 7. Thus, by the sealing element 5 de facto an at least in part enclosed first spatial region 6a is created, which is open towards an external environment of the battery pack 1 or the outer housing 2a, 2b, respectively, with respect to an exchange of liquid. A second spatial region 6b, by contrast, is separated from the first spatial region 6a in a liquid-tight manner. The second spatial region 6b may for instance be nearly hermetically closed against the external environment of the battery pack 1.

Water or other media penetrating the first spatial area 6a during operation of the battery pack 1 or the electrical appliance via the openings of the contact unit 9 or via the locking mechanism 12, are conducted in a defined way between the sealing element 5 and the sealing layer 7 and in particular kept away from the second spatial region 6b.

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As indicated in Fig. 4, the battery pack 1 for instance below the locking mechanism 12 comprises one or several drainage openings 10 for draining the first spatial region 6a.

As described with regard to the sealing element 5, also further sealing elements 5' may be applied as corresponding foam beads or the like to the top shell 2b or the sealing layer 7, as indicated in Fig. 5. Thereby, a further second spatial region 6c can be defined, which equally is separated from the first spatial area in a liquid-tight manner. Thereby, specific components, such as for instance the push button 14, which for functional reasons cannot be fully potted by the sealing layer 7, can be separated from the first spatial region 6a in order to prevent water from penetrating the region of the circuit board 4 underneath.

In Fig. 8 a sectional view through the fully mounted battery pack 1 of Fig. 7 is shown. Here, it is once again evident how the sealing element 5 and, if given, the further sealing element 5' are pressed by the web 8 of the top shell 2b to the sealing layer 7.

In various embodiments above the contact unit 9 or the contact elements 9a, 9b, 9c of the contact unit 9, respectively, a molded foam component (not shown) may be arranged, which may be designed to be in particular closed porous foamed and thus water-tight. The molded foam component comprises insertion slots for plug-in contact sheets of the electric power tool or the charging device for the battery pack 1, respectively. The plug-in contact sheets are wiped by the molded foam component during inserting. Thus, it is avoided that liquid or humidity is introduced at the plug-in contact sheets of the tools or the charging device into the region of the contact unit 9.

As described, the improved concept, allows for providing a battery pack with an improved sealing of critical regions against penetrating water and thus for improving the safety, in particular the functional safety, of the battery pack.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense,

17488002_1 (GHMatters) P115738.AU i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

17488002_1 (GHMatters) P115738.AU

Battery Pack for an Electrical Appliance

LIST OF REFERENCE SIGNS:

1 battery pack 2a bottom shell 2b top shell 3 battery cell 4 circuit board 5, 5' sealing element 6a, 6b, 6c spatial region 7 sealinglayer 8 web 9 contact unit 9a,9b,9c contact elements drainage opening 11 boundary element 12 locking mechanism 13, 14 push button 16 cell holder 17 connection contacts 18 electronic component 19 power MOSFET

17488002_1 (GHMatters) P115738.AU

EDITORIAL NOTE

APPLICATION NUMBER - 2021201701

Please note: Claims 1 and Claim 2 contain marked corrections.

Claims

Battery Pack for an Electrical Appliance CLAIMS:

1. Battery pack for an electrical appliance, the battery pack comprising - an outer housing comprising a bottom shell having a bottom, as well as a top shell; - at least one battery cell arranged in the bottom shell; - a circuit carrier arranged on a side of the at least one battery cell facing away from the bottom; and - a sealing element arranged between the top shell and a side of the circuit carrier facing away from the bottom, wherein - the sealing element separates a first spatial region within the outer housing in a liquid-tight manner from a second spatial region within the outer housing; and - the first spatial region is open towards an outer environment of the battery pack with respect to an exchange of liquid, - on a surface of the circuit carrier facing away from the bottom a sealing layer made of a liquid-tight material is arranged, which extends both in the first spatial region as well as in the second spatial region; and - the sealing element is in direct contact with the sealing layer for liquid-tight separation of the first spatial region from the second spatial region.

2. Battery pack according to claim 12, wherein the top shell comprises a web and the sealing element is arranged between the web and the sealing layer.

3. Battery pack according to claim 2 wherein the sealing element is pressed by the web to the sealing layer.

4. Battery pack according to any one of the preceding claims, wherein the sealing element comprises a sealing bead.

192261081 (GHMatters) P115738.AU

5. Battery pack according to any one of the preceding claims, wherein the sealing element comprises a foam material.

6. Battery pack according to claim 5, wherein the foam material is a plastic foam.

7. Battery pack according to claim 6, wherein the plastic foam is a polyurethane foam or a silicone foam.

8. Battery pack according to any one of the preceding claims, wherein the battery pack comprises a contact unit for electrical contacting of the electrical appliance and the contact unit is arranged in the first spatial region on the circuit carrier.

9. Battery pack according to claim 8, wherein the battery pack comprises a foamed material part covering the contact unit against the external environment and comprises at least one insertion slot for inserting a contact element of the electrical appliance into the contact unit.

10. Battery pack according to any one of the preceding claims, wherein the outer housing comprises a drainage opening, through which a liquid can drain from the first spatial region into the external environment.

11. Electrical appliance comprising a battery pack according to any one of the preceding claims.

12. Method for manufacturing a battery pack for an electrical appliance, wherein - a bottom shell for an outer housing of the battery pack is provided, which bottom shell comprises a bottom; - at least one battery cell is arranged in the bottom shell; - a circuit carrier is arranged on a side of the at least one battery cell facing away from the bottom; - a top shell for the outer housing is provided; - a sealing element is arranged between the top shell and a side of the circuit carrier facing away from the bottom; - the top shell is connected with the bottom shell;

19226108_1 (GHMatters) P115738.AU

- wherein the sealing element is arranged in such a way that it separates a first spatial region within the outer housing in a liquid-tight manner from a second spatial region within the outer housing, after the top shell was connected with the bottom shell, and the first spatial region is open towards an external environment of the battery pack with respect to an exchange of liquid; - a boundary element is applied to a side of a base plate of the circuit carrier; - a portion of the side of the base plate facing away from the bottom, which is bounded at least in part by the boundary element is coated with a potting material in order to create a sealing layer; - the coated portion extends both in the first spatial region as well as in the second spatial region.

13. Method according to claim 12, wherein the sealing element is applied as sealing bead on the circuit carrier or the top shell.

14. Method according to claim 13, wherein the sealing element is applied to the sealing layer in order to arrange the sealing element between the top shell and the side of the circuit carrier facing away from the bottom.

15. Method according to claim 14, wherein the sealing element is applied to the top shell in order to arrange the sealing element between the top shell and the side of the circuit carrier facing away from the bottom.

16. Method according to any one of claims 13 to 15, wherein the sealing element is arranged between a web of the top shell and the sealing layer.

17. Method according to claim 16, wherein the sealing element is pressed by the web to the sealing layer.

19226108_1 (GHMatters) P115738.AU